Extended range operation


Any flight by an aeroplane with two turbine engines where the flight time at the one engine inoperative cruise speed (in ISA and still air conditions), from a point on the route to an adequate alternate aerodrome, is greater than the threshold time approved by the State of the Operator.

Source: ICAO
Synonyms: extended twin-engine operation; ETOPS; extended range operation by twin-engined aeroplane